Plug



FIG. 1 is a front perspective view of a plug;

FIG. 2 is a back perspective view of the plug;

FIG. 3 is a top plan view thereof;

FIG. 4 is a bottom plan view thereof;

FIG. 5 is a left elevational view thereof;

FIG. 6 is a right elevational view thereof;

FIG. 7 is a back plan view thereof; and,

FIG. 8 is a front plan view thereof 

We claim the ornamental design for a plug, as shown and described. 